This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This protocol is a multicentered randomized double blind controlled 30-month study of Celebrex (celecoxib) in adult and pediatric patients with recurrent respiratory papillomatosis. The primary objective of the study will be to determine whether Celebrex, a selective COX-2 inhibitor, can decrease the rate of recurrence of visible papillomas in these patients. The study population will be patients age two or older with moderate to severe recurrent respiratory papillomatosis. All patients will be evaluated for disease severity at enrollment and at 3-month intervals for 30 months. Approximately 5 months after enrollment, patients will be randomized into either the early or delayed treatment group. Patients in the early treatment arm will begin celecoxib treatment 6 months after enrollment. The delayed treatment arm will begin celecoxib 18 months after enrollment. All adult patients will take Celebrex 400 mg once daily orally for 1 year. Children will take a reduced dose, determined by weight and age. During the time that patients do not receive celecoxib, they will receive a placebo capsule with the same appearance. Follow-up visits and endoscopies will occur at three-month intervals for the duration of the study.